Use ByteArray's native for Socket and File.

runtime/lib/byte_array.cc

Index: runtime/lib/byte_array.cc
===================================================================
--- runtime/lib/byte_array.cc	(revision 3706)
+++ runtime/lib/byte_array.cc	(working copy)
@@ -32,7 +32,7 @@
 
 static void RangeCheck(const ByteArray& array, const Smi& index,
                        intptr_t num_bytes) {
-  if ((index.Value() < 0) || ((index.Value() + num_bytes) > array.Length())) {
+  if (!Utils::RangeCheck(index.Value(), num_bytes, array.Length())) {
     GrowableArray<const Object*> arguments;
     arguments.Add(&index);
     Exceptions::ThrowByType(Exceptions::kIndexOutOfRange, arguments);
@@ -40,6 +40,25 @@
 }
 
 
+DEFINE_NATIVE_ENTRY(ByteArray_setRange, 5) {
+  ByteArray& dst = ByteArray::CheckedHandle(arguments->At(0));
+  GET_NATIVE_ARGUMENT(Smi, dst_start, arguments->At(1));
+  GET_NATIVE_ARGUMENT(Smi, length, arguments->At(2));
+  GET_NATIVE_ARGUMENT(ByteArray, src, arguments->At(3));
+  GET_NATIVE_ARGUMENT(Smi, src_start, arguments->At(4));
+  intptr_t length_value = length.Value();
+  intptr_t src_start_value = src_start.Value();
+  intptr_t dst_start_value = dst_start.Value();
+  if (length_value < 0) {
+    GrowableArray<const Object*> args;
+    Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
+  }
+  RangeCheck(src, src_start, length_value);
+  RangeCheck(dst, dst_start, length_value);
+  ByteArray::Copy(dst, dst_start_value, src, src_start_value, length_value);
+}
+
+
 #define GETTER(ArrayT, ObjectT, ValueT)                                 \
   GET_NATIVE_ARGUMENT(ArrayT, array, arguments->At(0));                 \
   GET_NATIVE_ARGUMENT(Smi, index, arguments->At(1));                    \